For Mountain Biking in Afghanistan

Few bicycle companies need to measure the size of an aircraft door when designing a new model. But Montague Corp., based in Cambridge, Mass., did exactly that when the Pentagon said it needed a lightweight, foldable bike that special-operations forces could carry as they jumped out of airplanes into enemy territory. In 1999 Montague came up with the Paratrooper, which has a hardened aluminum frame and wheels, and beefy pedals. It weighs only 29 lbs. and can fold in less than a minute to a manageable size (3 ft. by 3 ft. by 1 ft.). The market for parachutists' cycles being...